This invention relates to a disc cartridge, and more particularly to a disc cartridge which has a hard disc, particularly, a double-sided type hard disc housed in a casing.
In general, a disc-type data recording carrier such as a compact disc (CD), a video disc (LD) or the like is used in a manner to be removed from a packing case and set in recording and/or reproducing equipment.
Conventionally, its has been desirable to protect such a disc type recording carrier from environment because it is not only easy to be covered with dust and damaged but adversely affected due to a variation in temperature. For this purpose, the use of an envelope such as a tray, a casing or the like has been proposed to protect the disc. Unfortunately, such a conventional envelope is not suitable for the protection of a double-sided hard disc, because the the housing of the disc in a storage space defined in the envelope causes the disc to be contacted with the envelope. Also, the envelope causes the disc to be contacted with an inner surface thereof during the storage or transportation. Thus, the use of the envelope results in damage and/or pollution of the disc as well as the exposure of the disc to a variation in temperature. Further, when it is desired to support a photo-electro-magnetic disc of the double sided type in the envelope through as outer periphery of the disc, the envelope contacts any obstacle formed at the outer periphery of the disc such as an undesired protrusion formed due to mismatching, burrs or the like to cause crushing of the obstacle and/or misregister between the disc and the envelope.
Accordingly, it would be highly desirable to provide a disc cartridge which, even when any obstacle is formed at an outer periphery of a disc, is capable of preventing a casing from being contacted by the obstacle to safety keep the disc in the casing and hold the disc at a proper position in the casing.